Grinding wheel



p/id gm x v 5 H. E. HARRIS.

GRINDING WHEEL.

APPLICATION man APR. 14. 1919.

1,422,200. Patented July 111, 1922 II ll gxnamm g k 14 l 19 18 17 F: q- E J WITNESSES. l/VVE/VTOR A TTOH/VEY WANT @FFHCE.

GRINDING. WHEEL.

Specification of Letters Patent.

- Patented July 11, 1922.

Application filed April 14, 1919. Serial No. 289,963.

To all whom it may concern.

Be it known that I, HARRY E. HARRIS, a citizen of the United States, residing at Bridgeport, county of Fairfield, State of onnecticut, have invented an Improvement in Grinding Wheels, of which the following is a specification.

his invention relates to an improved grinding wheel and has for its object. to

provide such a wheel having'a large mass v and moment of inertia so that it will rotate heavy rim 16 the part 16' accurately on its axis. Another object is to provide a grinding wheel composed of a Wheel of steel or other metal carrying a disc or rin of abrasive material on'its'periphcry. E further object is to provide a wheel or ring of abrasive material varying in hardness in an axial direction, the hardest portion being preferably at the point of greatest diameter of the wheel, at the center thereof in the, example illustrated.

With these and incidental objects in view,

the invention consists in certain novel fea tures of construction and combination of parts which are set forth in the appended claims and a preferred form of embodiment whereof is hereinafter described with reference to the drawings which accompany and form part of the specification, wherein:

Fi l is a side elevation of a grinding wheeI embodying my invention, and

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1.

In said drawings the numerals 11 desig-' nate suitable bearings supported by bearing standards 12 mounted on )the base13. Said bearings receive the shaft 14 upon which the heavy gyro wheel 15, preferably formed of metal, is carried. This wheel maybe of any desired form except that the'mass is preferably I increase its moment of inertia. For this purpose the wheel may be formed with a of which may be removably attached thereto by suitable means as bolts 17 to clamp therebctween the disc or ring of abrasive material 18 in the recess 19. The disc or ring 18 may be formed of any suitable abrasive as emery, diamond dust, carbornndum, corundum, etc.,

but is preferably formed of harder material located as near the rim as possible to near its point of greatest diameter as shown by the darker porton 18. Any suitable means may be provided for rotating the wheel at a very high speed. y

In practice the gyro wheel 15 is very careflllllly made and accuratelyvbalanced, so that t e sibl'e with the axis of the rotating parts. On this account and on account of its great weight and large moment of inertia the wheel rotates very accurately in spite of possible play or looseness in the bearings. This is due in part to the well known tendency of a gyro wheel to resist a change in its plane of rotation. A further reason probably is, that as the critical is very low it will ordinarily operate far above this speed and its operation is therefore free from the vibration generally present when bodies are rotated below or near their critical speed. A further advantage is that a relatively small amount of abrasive material is necessary to secure the advantages of a grinding wheel of large diameter and a much smaller amount of abrasive is wasted, By forming the section corresponding to the position of largest diameter of harder material the wheel is better able to retain its original contour as the greater tendency to wear at the point of for by greater durability at this point. It will be seen that I have provided a con- "struction which fulfills the objects previously statedand while I have shown and described a specific embodiment of my invention it is to be understood that changes and modifications thereof may be made without departing from my invention as defined in the following claims I claim:

1. A rinding device com risin a ro wheel having. a wide, sub tantia lly fi at, heavy periphery composed of two sections substantially equal in mass, one of said speed of such a wheelgreatest diameter is compensated sections having a peripheral recess, a ring of abrasive material mounted in said recess, ahd means to clamp the other of said sections against said ring and ring holding section.

2. A ring of abrasive material having por wheel and a ring of abrasive material earried thereby portions of the grinding surface of said ring being of greater diameter than other portions, the portions of greater diameter being composed of harder material.

si nature.

In testimony whereof I aflix m A BIS.

HARRY E. 

